1. Stand on the lowest step of a staircase, facing the stairs; hold on to a railing for balance. Place the balls of your feet on the edge of the step so your heels hang off.

2. Slowly raise your heels up as high as you can, then lower them down as far as you can. Do as many repetitions as possible. (If you don’t feel steady on a step, try doing the move with both feet on the floor instead.)

1. Get into a boxing stance with your feet hip-width apart, elbows close to your body and fists in front of your face.

2. Take one step back with your left leg and bend your knees slightly. Throw a punch with your right hand, reset, then throw a punch with your left hand as you rotate your torso to the right. Throw a total of 10 punches, then switch your stance and do the opposite, stepping back with your right foot.

3. Alternate stances every 10 punches; box until slightly fatigued.

1. Stand with your back straight, feet hip-width apart, arms at your sides.

2. Step forward with your left leg, leaning forward until your left knee is above your toes. (Your right leg should be as straight as possible behind you, right heel raised off the floor.)

3. Push yourself back up into the starting position. Now repeat the move, this time stepping forward with your right leg and keeping your left leg straight. Continue alternating between your left and right leg for as many repetitions as possible.

1. Stand straight with your arms by your sides, palms facing inward.

2. Rotate your forearms in a small circle and hop as though you’re skipping rope, keeping your legs and feet slightly apart. Keep your head facing forward. Only hop off the floor an inch or so and land on the balls of your feet to reduce stress on your knees.

3. Continue jumping at a comfortable pace until slightly fatigued.

Myatt Murphy is the author of nearly two dozen books on health and fitness.